Oxford scientists are trialling a new approach to disease prevention in Juazeiro, Brazil after the Dengue Fever endemic spreads to more than 110 countries.
An Oxford firm, Oxitec, has developed a genetically modified A. aegypti mosquito, OX513A that requires a chemical supplement of tetracycline to develop beyond the larval stage. Males are selected to be supplied with this chemical and released into Dengue fever endemic test areas on-mass to populating the breeding pool with the modified tetracycline-dependant strain, impregnating females but producing invalid offspring. A 2010 test site on the Cayman Islands where 3 million OX513A were released reports a wild population drop of 80%.
Dengue Fever is a tropical disease caused by any 1 of 5 strains of the dengue virus, symptoms include fever, joint pain and skin rash but can develop into deadlier versions of the virus, including dengue haemorrhagic fever and dengue shock syndrome. The virus is mosquito borne and along with the principle transmission species Aedes aegypti has spread into new tropical and subtropical areas, including Queensland, Australia and limited cases in Florida, and infects 528 million people yearly. The increase is documented as due to population growth, increased international travel and global warming.
There is no commercially available vaccine.